1. Field of the Invention
The present invention relates to a method of manufacturing a connector and to a connector manufactured by the manufacturing method.
2. Description of Related Art
There is known a differential transmission system adapted to transmit a differential signal pair, comprising signals having opposite phases, in two signal lines forming a pair. Since the differential transmission system has a feature that the data transfer rate can be made high, it has recently been put to practical use in various fields.
For example, in the case of using the differential transmission system for data transfer between a device and a liquid crystal display, the device and the liquid crystal display are each provided with a display port connector which is designed according to the display port standard. As this display port standard, VESA DisplayPort Standard Version 1.0 or its Version 1.1a is known.
This display port connector is a kind of differential signal connector and has a first connection side for connection to a connection partner and a second connection side for connection to a board of the device or the liquid crystal display. The configuration of the first connection side is strictly defined by the display port standard in terms of the relationship with the connection partner while the configuration of the second connection side is relatively free. This type of differential signal connector is disclosed in Japanese Patent (JP-B) No. 4439540 (Patent Document 1) and comprises a shell and a contact group held by the shell.
The contact group disclosed in Patent Document 1 comprises, as shown in FIG. 1, three ground contacts 1 arranged at regular intervals and two pairs of signal contacts 2, each pair being arranged between the adjacent ground contacts 1. On the first connection side of the connector, first ends 1a of the ground contacts 1 and first ends 2a of the signal contacts 2 are adjacently arranged on a straight line. Then, the ground contacts 1 and the signal contacts 2 extend in parallel to each other and then are bent at a right angle in the same direction at positions offset from each other. As a consequence, on the second connection side of the connector, second ends 1b of the adjacent ground contacts 1 are located at both ends of the long side of a trapezoid while second ends 2b of the signal contacts 2 forming each pair are located at both ends of the short side of the trapezoid. Then, the second ends 1b of the ground contacts 1 and the second ends 2b of the signal contacts 2 are respectively inserted into through holes of a connection object and are connected to the connection object by soldering.
According to the contact group described above, since, on the second connection side, the second ends 1b of the ground contacts 1 and the second ends 2b of the signal contacts 2 are arranged in different rows so that the distances therebetween are increased, the operation of connecting them to the connection object is facilitated.
On the other hand, JP-A-H03-30274 (Patent Document 2) and JP-A-H06-13154 (Patent Document 3) disclose a technique that prepares a plurality of contact assemblies, as intermediate members, each having a plurality of wide-pitch contacts by pressing separate metal plates and then combines them together, thereby narrowing the array pitch of the contacts.